'Decision-theoretic paradoxes as voting paradoxes'

Whoa, no. That's a bad mantra. Wireheading, quantum immortality, doing meth - these are bad things.

Briggs is here primarily considering cases where your preferences don't change as a result of your decision (but where your credences might). If we're interested in criticising the argument precisely as stated then perhaps this is a reasonable criticism but it's not an interesting criticism of Briggs' view which is to do with how we reason in cases where our decision gives us new information about the state of the world (ie. about changing credences not changing utilities).

This not only requires you to throw away the cardinal information as gwern says

Again, it is not clear that this is an interesting criticism. The result doesn't rely on cardinal values but it does apply to agents with cardinal values. This makes it a stronger more powerful result (rather than an uninteresting result which doesn't apply to actual theories). The result only relies on the ordinal rankings of outcomes but it causes problems for theories that utilise cardinal values (like decision theory). So Gwern notes that "a lot of voting paradoxes are resolved with additional information. (For example, Arrow's paradox is resolved with cardinal information.)". This isn't true with Briggs' argument - it can't simply be resolved by having cardinal preferences.

A reductio ad absurdum of this position would be that it can't even distinguish CDT from evil-CDT, which is where you always choose the locally worst option. Their result is really just the statement "some decision theories have different preference orderings,"

Again, not clear that this is an interesting criticism. Briggs' isn't trying to develop a necessary and sufficient criteria for theory adequacy so it's no surprise that her paper doesn't determine which of CDT and evil-CDT one should follow. She's just introducing two necessary criteria for theory adequacy and presenting a proof that no theory can meet these. So both CDT and evil-CDT fail to be entirely adequate theories - that's all she is trying to establish. Of course, we also want a tool that can tell us that CDT is a more adequate theory than evil-CDT but that's not the tool that Briggs is discussing here so it seems unreasonable to criticise her on the grounds that she fails to achieve some aim that's tangential to her purpose.

I'm not convinced that Briggs' argument succeeds but I take it that the argument is meant to apply as long as the theory ranks decisions ordinally (rather than applying only if they do so and not if they utilise more information). See my response to manfred for a few more minor details.

This is just another attempt to use English to wrestle with problems that become trivial when you restate them in a programming language. And I think we have more than enough of those already.

Disagree. From my perspective at least the central idea- of treating different decision theories as voting by potential future selves seems to be a novel and interesting idea. Moreover, while they don't state things in terms of programming languages, they are sufficiently precise with a lot of their discussion that I don't think they are running into many problems arising from language. Some of their remarks may however be better stated in a more algorithmic approach.

For a moment I thought "deine" was some kind of new high-concept philosophical jargon.

E.g. it is hard to find scales where you can't usefully use economics, or ecology, or complex systems, etc.